Every child has dreams. Most children, at some point in competition soccer, say they want to be a member of the National Team or they want to play professionally. Let them dream. Dreams are what excite kids to work hard. Dreams are the very thing that makes your child happy and wanting to do the things to achieve the dream.
They are only children once and they should have the right to dream they can be anything they want. Believe me, their dreams will probably change when they figure out that there is something they want more than to play professionally. The hard reality of being "the best" in competitive soccer, will come soon enough.
Remember their dreams are their dreams. Your dreams are your dreams. Sometimes it's easy to get the two confused. What you view as success might not be your child't view of success. Let your child dream they way they choose to dream. Don't tell them what and how to dream. Support their dream but don't usurp their dream. A nine-year-old should not be training like a High School Senior. Remember your child is a child, and not someone for you to live your dream through.
Until they decide what they want when they are older, let them dream their own dreams.